Against

Centralised AF point arrangement, autofocus system not as fast or customisable as competition, AF point adjustment shows in black which can be hard to see, battery life really doesn't cut it, limited buffer feels inconsistent with burst feature, pricey, auto white balance often off the mark, AF-D (3D tracking) not compatible with full lens range

We knew the Sony Alpha A99 - the first full-frame single lens translucent (SLT) camera - was on its way, having played with it extensively back in 2012. Sony's transition from the traditional DSLR space to the SLT fold has seen the company make the digital DSLR, well, even more digital in many respects. In our minds the Alpha A99 represents the completion of that process of change; it's out with the old A900 and traditional DSLR cameras as a whole, and in with the new tech.

The big question is whether SLT is ripe and ready for its place in a full-frame package. Has the Sony A99, like that other famous 99, topped off the company's Alpha range with a proverbial chocolate Flake of digital goodness, or does the very nature of an SLT design hinder more than progress at this level?

Mirror, mirror in the camera

The SLT concept is an interesting one. By using a translucent mirror the A99 removes the necessity for it to move in order to get light to the sensor, ie, to take a shot. This means continuous autofocus while burst shooting is possible without interruption as mechanical movement is restricted to the shutter. Hurrah, success, a technology that adds a fistful of sweetened sprinkles to the A99's feature set.

But it's not totally sugar-coated. The drive mode's maximum six frames per second (6fps) burst mode topped out at 11 JPEG frames total when using a class 10 card, which isn't that much ahead of the years-old Alpha A900 which the A99 replaces. The single Bionz processor and buffer just doesn't seem that well paired to the A99's potential. There is also an 8/10fps option available but only when using the dedicated 1.5x crop mode on the mode dial.

What's sweet to some is sour to others, and that's the outlook for the A99's viewfinder. While the camera's internal mirror still bounces light to an autofocus sensor, as per a DSLR, there's not enough light to feed an optical viewfinder so an electronic one is used instead. That's why an SLT is a kind of "digital stacked on digital" camera. It's also why some prospective customers might not feel compelled to buy.

Why so? Simply because some people don't like the feel of an electronic viewfinder. The way it shows up image noise in low light and displays some ghosting lag when panning are two distinct points to be aware of, plus it's a continual and unavoidable battery drain.

However the advantages of real-time colour and white balance, exposure, electronic levels and playback options can be useful to some degree. Exposure and auto white balance will adjust in real time, yet it is not possible to see pre-set selections directly to the eye - that'll need the picture to be shot and processed before it's then shown back in the viewfinder. Yet this quick shot-to-eye playback - which can be disabled if not wanted - will give an accurate rendition of the exposure, white balance and so forth, meaning that quick adjustments can be made there and then without the need to remove the camera from the eye. Depth of field preview also doesn't suffer from any "dimming" irrelevant of the aperture selected, as the EVF is able to compensate. To some these features will stack up as positives above and beyond what an optical finder can offer.

In the case of the A99 the electronic viewfinder is as good as they currently come. It packs in 2.35-million dots so there's no denying its crisp resolution and it handles panning as well as any that we've seen, though it's still not perfect and doesn't have quite the same smoothness as an optical equivalent. The 0.71x magnification and 0.5-inch display puts the A99's 100 per cent field of view up there with the likes of the Nikon D800 and similar full-frame competitors.

Pushing forward, yet sliding back

When we first saw the Sony Alpha A99 in 2012 in Iceland it left us feeling a little cold. And it was nothing to do with the weather - its dual-AF system that combines 102 sensor-level phase-detection pixels and a 19-point AF module tried to walk the walk but, in the end, we just didn't find the A99 to be fast enough to cut it at this level. At least not at that stage in production.

But enter the final shelf-worthy model of the camera and it's stepped things up a gear. Paired with the 24-70mm f/2.8 Sony/Zeiss lens and we've been pleased with the swiftness of the response in comparison to the state in which we first saw the camera. This is also one of six current lenses that work with the Sony's 3D tracking system, known as AF-D.

But that's not to say there aren't issues. The 19-point module, which houses 11 cross-type sensors, is centrally arranged - and we mean very much so - without the kind of reach that we'd expect from Sony's top tier digital interchangeable lens camera. When selecting a focus point it also shows up in black, not a bright colour such as red which, on a dark background, makes it tricky to see.

Compared to its rivals too - which include the Nikon D800 and Canon EOS 5D Mark III - the Sony's focus system doesn't feel as fast, irrelevant of its dual-AF hype. The cross-type sensors also aren't as sensitive and when shooting in low light - and this is possibly due to the limited amount of reflected light from the translucent mirror - it's not uncommon for autofocus to struggle. The maximum f/2.8 sensitivity is restricted to the centre focus point, so the spec is closer aligned to that of the more budget Canon EOS 6D.

None of this would be much of an issue if the camera wasn't pitching itself against some very strong and similarly priced rivals. At the time of writing the D800 is a couple of hundred pounds less to buy, while the 5D MkIII is about £100 more than the Sony.

Another significant issue with an SLT build is the amount of power that is constantly in use, and therefore the A99's battery life isn't up to where we think it should be. As either the rear screen or the viewfinder screen is always on, not to mention the processing demands of the full-frame chip - note this is a single Bionz processor, not a dual processor like the A900, presumably to try and cut back on power consumption - there's an ongoing battery drain.

At under 500 shots per charge, more like 450 in the real world, the A99's battery life is around half that of its main two rivals. As a camera knocking on the door of pro-spec that's really not good enough. There is an optional battery grip which, according to Sony, takes three additional batteries (we think it's two though) that may come to your rescue, but it comes at a price - £250 plus around £70 per each battery to put in it.

D'ya wanna flake in that luv?

There are some top features also packed into the Sony A99, including the rear LCD screen's vari-angle bracket. No other full-frame camera has such a feature, which makes the A99 stand out as unique.

To the front of the camera there's also a silent adjustment dial that's great for not only making adjustments in movie mode without causing a sound, but can also be programmed to adjust other key settings when shooting stills. It's an invaluable function button, above which there's a second "C" function button near to the camera's "a99" logo.

Another cool new feature is what Sony calls "AF Range". It's fairly self explanatory - the press of a button allows you to limit the focus range within defined parameters, whatever lens is on the front of the camera. We were already impressed with this upon our first use, given the practical applications when shooting through wire fences, dirtied-up glass, or where other subjects will pass through the frame but you wish to ignore them.

As per other Sony cameras there's also a tele-zoom button that can magnify by 1.4x or 2x when shooting JPEG files. Doing so will crop into the frame so the resulting shots are lower resolution but not lower quality. It's a great way to get more reach out of any given lens. It's a shame there's no compatibility when shooting raw files - not even necessarily because we'd want the raw equivalents, more because switching out of raw & JPEG mode to be able to use the tele-zoom is a big slow down because of the menu trudging required.

The A99 offers dual SD card slots or you can use MemoryStick Pro instead. Given the camera's buffer limitations the addition of an XQD or other card format slot probably wouldn't have added much advantage. It does seem a little odd for Sony to shun its own speedy card format in its highest-spec digital camera though.

Built-in GPS can also come in handy, but it is another battery-munching feature for the sake of geotagging shots.

Punchy pictures

There's a lot to be said for full-frame image quality, and the A99's 24-megapixel sensor is certainly able to produce the goods. There's no disputing that the sensor can output shots of equal quality to that of the Nikon D600, Canon EOS 5D Mark III and other similar competitors at its lowest ISO settings. Shots are resolute and detailed throughout.

However we did find there to be a hint of colour noise visible from within many shots, including down to ISO 400, which may come as a disappointment for those looking to the full-frame market for cleaner shots than an APS-C counterpart. We're not talking disruptive levels, but it's still a subtle presence.

ISO 800 at 100 per cent crop

It's at the higher ISO settings where image noise becomes an inevitable issue. While the A99 is capable of shooting up to ISO 25,600 we wouldn't recommend it. Indeed, inclusive and upwards of ISO 6400 we'd say that the Sony presents more colour and luminance noise than its nearest competitors, though only by a smidgen.

ISO 3200 (full image)

Sony's processing gives shots a distinctive colour presence and punch, although we weren't always impressed with the auto white balance accuracy, and JPEG frames tend to be contrasty - something that can be adjusted for from within the JPEG settings and presets.

Movie mode magic

Here's an area where the A99 is extra tasty. As well as 1080p capture at 60/50/30/25/24fps - take your pick - there is also a 3.5mm microphone input and another 3.5mm for headphones monitoring. Pros will also be keen to see an HDMI output which can cater for clean, uncompressed output that's perfect for capturing footage to an external recorder.

On the front of the camera there's the silent mode dial which is silent when rotated and has a soft press function button to its front too. It's a mini revelation really, the likes of which has never made it to a DSLR camera before. It can be programmed as required for adjustments during capture, including making focus type adjustments live during recording.

Not only is it possible to utilise continuous focus which, thanks to the SLT design is significantly beyond that of other interchangeable lens cameras in speed terms, but the design also means either the electronic viewfinder or screen view can be used during capture. This is where the camera really comes into its own.

Quality is cracking too, with the maximum 28Mbps data rate plugging plenty into the AVCHD captures. If the data rate was beyond the 50Mbps marker and offered a variety of format captures too then the Sony would be unrivalled. Small room for improvement, but otherwise an attractive movie capture prospect, save for potential battery life limitations.

Verdict

Taken in isolation and the Sony Alpha A99 has the makings of a great full-frame camera: sturdy build, a fast burst mode, decent image quality and an excellent movie mode are polished up all the more by quirky additions such as the silent mode dial, tele-zoom mode, built-in GPS and a vari-angle-mounted LCD screen. There are things here that no other full-frame camera offers, and others - such as the burst mode - that are, at least on paper, more familiar of a pricier pro body.

But for all its sweetened marvels, there are limitations in key areas at almost every turn. The autofocus system, while certainly capable, hypes itself up with its dual-AF technology but, ultimately, comes up behind the competition's systems. The main focus points are also arranged too centrally - just like that of the Alpha A77 - and the sensor-level phase-detection pixels don't seem to add anything to the party, nothing that we could notice with a compatible lens anyway.

The fast burst mode may be one of the A99's killer modes, as that's what SLTs can do so well, but it's partially maimed by the camera's limited buffer. We're sure Sony could have squeezed more out of this, as it's not even as rapid as the Alpha A77.

And then there's the A99's battery life. Oh the battery life. It's miles off the mark compared to the competition, which feels mismatched for a pro-spec body that's built to cater for shooting bags of images in all kinds of conditions. We'd recommend the battery grip, but this comes at a cost.

It's hard to argue with the A99's pictures, although we did find there to be slightly more visible colour noise than the nearest (and cheaper) competition.

From a movie capture point of view we're impressed with the A99 beyond all its peers, largely because of the continuous autofocus and abundance of controls on offer. For a capable and easy-to-use movie capture system we can see this Sony scoring highly with videographers. Yum.

This particular 99 is all cone and Flake - it's a scoop short in a handful of key areas and, in particular when considering its nearby competitors, comes at a price that's a big push too. We don't doubt it can succeed as a top-spec workhorse, but relative to what else is out there feel there are a couple of hiccups that cost this release.

Gaming geek, semi-failed cyclist, big screen and movie lover and fan of both big beats and beer. As the former Reviews Editor at What Digital Camera, self-confessed camera geek Mike has seen pretty much every digital camera that's been made. His work has featured in a variety of well-respected titles, including Wired, TechRadar, Professional Photographer and many more.